Thursday 3 June 2010 14.14 EDT
First published on Thursday 3 June 2010 14.14 EDT

Paul Chambers, a former trainee accountant who was fined £1,000 after posting a message to the social network Twitter joking about blowing up an airport, is to appeal against his conviction.

Chambers was found guilty in May of sending a message of a "menacing character" under the Communications Act 2003 after he tweeted in frustration in January at the closure of Robin Hood airport, near Doncaster, owing to snow. "Crap! Robin Hood airport is closed. You've got a week and a bit to get your shit together, otherwise I'm blowing the airport sky high!" he wrote, frustrated that his plans for a flight to Ireland looked like being thwarted.

The appeal, which is likely to be heard next month or August, is being co-ordinated by Allen Green, a prominent lawyer who writes the Jack of Kent blog, and will be led by Stephen Ferguson, a leading defence barrister who is being paid from a defence and appeal fund for Chambers.

The arguments will turn on whether the message could reasonably be interpreted as menacing under the terms of the legislation.

Writing on his blog, Green says: "I think that we can be optimistic for Paul's chances on appeal, but that sadly is not a certainty. There is still a lot of work to be done so that this injustice can be remedied."

After the initial verdict at a magistrates' court, Chambers admitted that his tweet was "silly" but called the police reaction "absurd", saying his tweet was "like having a bad day at work and stating that you could murder your boss" and that "I didn't even think about whether it would be taken seriously."

Chambers left his job as a financial supervisor at a car distribution company after having been arrested in January at work by four police officers. His solicitor in the initial case argued that the tweet was a "Basil Fawlty" outburst – immature, tasteless, unacceptable, but not criminal. The airport itself described the message as "not credible" as a threat, and its operations were not disrupted, but it was obliged to tell South Yorkshire police. They took a different view.

"I would never have thought, in a thousand years, that any of this would have happened because of a Twitter post. I'm the most mild-mannered guy you could imagine," Chambers said after the initial verdict.